Sort administrator UIDs for NetworkCapabilities.

Administrator UIDs stored in NetworkCapabilities should be sorted. This
allows for easier equals checks and hashCode computation. Additionally,
duplicate UIDs should be prevented.

Bug: 147903575
Test: atest FrameworksNetTests
Change-Id: Ia5387ca2ce7c3fcbd04dc7fbff5266f7bcc71694

core/java/android/net/NetworkCapabilities.java

@@ -909,6 +909,7 @@ public final class NetworkCapabilities implements Parcelable {
      * <p>The administrator UIDs are set by network agents.
      *
      * @param administratorUids the UIDs to be set as administrators of this Network.
+     * @throws IllegalArgumentException if duplicate UIDs are contained in administratorUids
      * @see #mAdministratorUids
      * @hide
      */
@@ -916,6 +917,12 @@ public final class NetworkCapabilities implements Parcelable {
     @SystemApi
     public NetworkCapabilities setAdministratorUids(@NonNull final int[] administratorUids) {
         mAdministratorUids = Arrays.copyOf(administratorUids, administratorUids.length);
+        Arrays.sort(mAdministratorUids);
+        for (int i = 0; i < mAdministratorUids.length - 1; i++) {
+            if (mAdministratorUids[i] >= mAdministratorUids[i + 1]) {
+                throw new IllegalArgumentException("All administrator UIDs must be unique");
+            }
+        }
         return this;
     }
 

tests/net/common/java/android/net/NetworkCapabilitiesTest.java

@@ -441,6 +441,23 @@ public class NetworkCapabilitiesTest {
         return range;
     }
 
+    @Test
+    public void testSetAdministratorUids() {
+        NetworkCapabilities nc =
+                new NetworkCapabilities().setAdministratorUids(new int[] {2, 1, 3});
+
+        assertArrayEquals(new int[] {1, 2, 3}, nc.getAdministratorUids());
+    }
+
+    @Test
+    public void testSetAdministratorUidsWithDuplicates() {
+        try {
+            new NetworkCapabilities().setAdministratorUids(new int[] {1, 1});
+            fail("Expected IllegalArgumentException for duplicate uids");
+        } catch (IllegalArgumentException expected) {
+        }
+    }
+
     @Test
     public void testCombineCapabilities() {
         NetworkCapabilities nc1 = new NetworkCapabilities();